This invention relates generally to methods and apparatus for providing shock protection to breakable electronic assemblies in a casing, while, at the same time, conducting heat away from heat generating components of the electronic assembly. Methods and apparatus of the present invention are particularly useful in the field of medical imaging, but can be applied to other fields as well.
In various portable medical imaging applications, an air-cooled x-ray detector array is sealed in a casing that is typically formed of metal. The x-ray detector array includes a scintillator array on a breakable glass panel. The glass panel is affixed directly or indirectly to a circuit board that includes heat generating components. The heat generating components are thermally coupled to the casing via a thermal compound that is not shear resistant, meaning that the thermal coupling could be broken when shear forces are applied.
The x-ray detector array and an x-ray source are positioned on opposite sides of a patient to collect medical images of the patient. In most uses, data is collected once or infrequently from the detector array. Thus, heat generated by the heat generating components usually remains nominal. However, other uses of large x-ray detector arrays, e.g., uses that provide a more constant data stream (such as for full-motion and/or contrast agent imaging) are emerging. These uses generate a rather considerable amount of heat that must be conducted away.
In order to simultaneously isolate the x-ray detector array from mechanical shock loading and thermally manage component and detector array temperatures, it would be desirable to allow the detector array to move relative to the casing to some extent while absorbing the shock load to reduce maximum acceleration delivered to the detector array. In addition, it would be desirable to interface the heat generating electrical components to the casing using a thermal compound. In addition, it would be desirable to provide a lighter detector than is now available. However, the thermal compound will be in shear when the detector array is dropped, accidently or otherwise. The thermal compound will not be able to endure the expected large deflections. Also, when the detector array is dropped, a shock is delivered to the casing. To isolate the glass panel from shock and breakage, internal movement of the glass panel relative to the covers is desirable.